Bathed in a golden Olympic afterglow, London is winning yet more plaudits for selling record numbers of tickets for the Paralympics. The authorities are preparing a victory parade of medalists from both events. Critics have fallen silent. National pride is, rightly, swelling. But remember, if you will, a time when the city’s bid to host the 2012 Summer Olympics and Paralympics looked doomed, like so many British sporting efforts, to end in noble failure. Ahead of the International Olympic Committee’s decision in July 2005, Paris was the firm favorite. Then, in the last ballot, London edged its rival by four votes. The factor that pushed wavering members of the IOC into London’s corner? Its backers’ pledges of a substantial and lasting legacy.

It was a clever move, and one that chimed with Olympic ideals. “London’s vision is to reach young people around the world,” said Seb Coe, who led the British bid and later became chairman of the Games’ organizing committee. “To connect them with the inspirational power of the Games, so they are inspired to choose sport.”

Here’s another ambitious pledge made that day: “The regeneration of the area around the Olympic Park is already under way…The Games will dramatically improve the lives of Londoners.” The speaker was the mayor of London—not Boris Johnson, the current incumbent who presided over the Games, but his predecessor Ken Livingstone, ousted in elections in 2008.

And unlike most talk of legacy, the first part of Livingstone’s claim was tangible. A chunk of the East End, an area blighted by the decline of the docks that once fueled its economy and the collapse of manufacturing industries that took up some of the slack, was already in the throes of transformation. The boost from the Olympics sped that change. You feel it in the air-conditioned comfort of the high-speed Javelin trains serving, since July, the Stratford station complex that is the main gateway to the Olympic Park and linking the area to central London and the south coast of England. You can walk through 175,000 square meters (that’s 1.88 million square feet for imperialist readers) of Westfield Stratford City, a high-end shopping mall opened in September 2011. From its food court, you see, stretching out into the distance, the Olympic Park, a gleaming collection of new buildings that promise enduring tourist attractions, sports facilities and entertainment venues, office space and mixed income housing.

The Olympics has alighted on the boroughs of Newham, Tower Hamlets and Hackney, as I wrote in a piece ahead of the Games, like an enormous, shiny spaceship. But leave its confines and you’ll begin to understand the scale of the challenge to be met if locals, much less London’s further-flung populations, are to see their lives dramatically improved. In March I accompanied housing enforcement officers and police during raids on slum properties in Newham. A garden shed, converted without insulation, provided cold comfort for four young Asian men, at a cost of £800 (US$1,268) per month, they said. The tenant in a Union Jack T-shirt who opened the door to a nearby two-bedroom terraced house was less forthcoming, but his hacking cough told a story (“tuberculosis is rife in these places,” said one official). The arrangement of bedding suggested as many as 18 people had taken lodging on the premises, lining the pockets of an unscrupulous landlord who will understand that the powers of the authorities to intercede are limited and the appetite to do so also circumscribed. “If every London borough rooted out baleful practices such as these, a significant number of people would be revealed who would then need to be rehoused,” says Tony Travers, the director of LSE London, a research center at the London School of Economics.

Newham is working to tackle its slum landlord problem and to find innovative ways of increasing its stock of affordable housing; it had schemes before the Olympics to engage kids from hardscrabble backgrounds in sport and music. But another way to reduce the press of people looking for the cheap accommodation is to attract more affluent residents and retain the upwardly mobile. “I bought a house with a not-very-nice front; it was a mess, [it was] three weeks before the smell of piss was gone from the garden,” said Robin Wales, the mayor of Newham when I met him back in March. “But my neighbors have done up five houses on their side and it looks quite nice. When you get that investment in the look of it, the whole area starts to turn.”

“The Olympics is regenerating the area we have been regenerating anyway,” he added. “[But] it will be done faster. It has moved much quicker.”

But will regeneration benefit the people living outside the spaceship? Some of them, at least. Unemployment rates in Newham are among London’s highest. My unscientific survey of Westfield mall employees failed to turn up a single local, but several thousands of Newham residents have reportedly found jobs there and others were involved in readying the Olympic Park.

My survey also revealed that people working and shopping in Westfield rarely venture beyond its glossy boundaries. They were unaware of the mall’s alter ego, just a pole vault across the road. Gold and silver jewelry is on sale at the Stratford Centre, opened in 1974. But a tranche of these wares are second-hand, pawned by their owners for cash. A discount chain, Poundland, competes with a branch of a rival chain whose name promises yet bigger bargains: a 99p Store. (What can you get for 99p/$1.57? A wide range of products including a buoyancy aid called a Super Swim Noodle and a large family pack of the traditional English cookies, Custard Creams.) In the two malls, old Newham and new Newham coexist, side-by-side, but rarely intersecting.

That is a pattern often seen in gentrifying urban areas. One question that will determine the extent of the gentrification is whether the communities begin to integrate and stabilize. One question that will determine the truth of Livingstone’s IOC promise is what will happen to those people outside the spaceship as it extends its tentacles. Here, as in so many assessments of the Olympic legacy, there will be no swift or definitive answers. Let the guessing Games commence.